India has reduced its purchases of Iranian oil, but has been in talks on extending a sanctions waiver, known as a significant reduction exception, a senior official in India said in January, Reuters reported.
The talks come just as trade tensions rise between Washington and New Delhi. The United States is planning to end preferential trade treatment for India that allows duty-free entry for up to $5.6 billion worth of its exports to the United States.
India is the biggest beneficiary of the Generalized System of Preferences, which dates from the 1970s, and ending its participation would be the strongest punitive action that Washington has taken against the country since President Donald Trump took office.
Amid this, New Delhi is asking Washington to be allowed to still buy Iranian oil at current levels of around 1.25 million tons per month, equal to about 300,000 bpd, the sources said.
The United States reimposed sanctions against Iran last November after Trump pulled Washington out of the 2015 nuclear deal between Tehran and six world powers.
Vincent Campos, a spokesman at the US State Department's energy bureau, would not confirm that India was asking the United States to renew its waiver, but said talks are ongoing with the eight consumers of Iran's oil that received waivers in November with the aim of eventually cutting imports to zero.
"We continue to have bilateral discussions" with each of the countries, including India, Campos said.
A US State Department official is this week visiting South Korea, Iran's fourth largest oil customer in Asia, to talk about sanctions, Seoul said.
David Peyman, a deputy assistant secretary for counter threat finance and sanctions, met on Wednesday with Hong Jin-wook, an official specializing in African and Middle Eastern affairs at South Korea's foreign ministry.
Peyman offered "to continue to closely consult on the extension of sanctions exemption and Korean companies' technical issues regarding trade with Iran," a statement from Seoul's foreign ministry said.
The US State Department did not immediately respond to questions about their talks.
Iran, a member of the Organization of the Petroleum Exporting Countries (OPEC), exported almost 3 million bpd of oil at its pre-sanctions peak, but that has dwindled to around 1.25 million bpd since the start of the year, shipping data from Refinitiv showed.